Clinton added that she wanted to test Myanmar's commitment to both economic and political reform. "How real it is, how far it goes -- we will have to make sure we have a better understanding than we do right now," she said.

What concessions has Myanmar's government made?

One of the first came with the election last year of former Gen. Thein Sein as the country's president, albeit in a vote called by the country's military rulers and at the time slammed by Obama as a "sham" election.

Days after the vote, the new government released longtime political prisoner Aung San Suu Kyi, whose party, the National League for Democracy, recently announced its intention to contest upcoming parliamentary elections.

One of the president's political advisers, Nay Zin Latt, recently told the Wall Street Journal that the country's reform process was "not (in) the initial stage. It would be in the middle of the democratization process."

Last month, dozens of other political prisoners were released, and there are promises that more will follow. This is viewed as a huge step forward for a country that previously denied that it imprisoned people for their political views.

There have been calls for greater press freedom from the head of state censorship, and Human Rights Watch reports that the government has passed reforms protecting basic human rights. However, the group has also noted that the government retains tight control over the country.

What is the reaction to Clinton's visit inside Myanmar?

"A lot of people inside Burma are very excited," said Aung Zaw, editor of Irrawaddy Magazine, adding, "I think it's a huge, major development."

Irrawaddy Magazine was founded in 1993 by a group of Burmese journalists living in exile in Thailand, who say they aspire to report news from Myanmar without political interference.

Aung Zaw says Clinton's arrival is a victory for Myanmar's new government, which yearns for international approval despite international criticism that it was elected by a vote that was neither free nor fair.

"They are craving for international legitimacy and recognition, and this visit will boost the government's ongoing reform process and legitimacy, no doubt about it," he said.

How has China, Myanmar's longtime ally, reacted?

In the days leading up to Clinton's visit, China's Vice President Xi Jinping, who is also vice chairman of the Central Military Commission, emphasized the close relationship between China and Myanmar and the country's commitment to deepening their ties.

"China will work with Myanmar to further bolster the comprehensive strategic partnership of cooperation," he was quoted as saying by Chinese state-run news agency Xinhua.

Myanmar shares a border with China, which became an important source of trade and investment for the country during its years of isolation from the West.

Aung Zaw says Myanmar will need to engage in "delicate and sophisticated" diplomacy to retain its close ties with China while improving its relationship with the U.S.

After years of isolation, why change now?

"There's a realization from the government as well as the opposition that it has to change: 'We can't keep going on like this,' " Aung Zaw said. "So I think also there's their own self interest, geo-political strategy concerns and a combination of pressure from inside and outside."

He says it's in Myanmar's interests to nurture a relationship with the U.S. to balance its close ties with China.

"Burma will have to maintain a good relationship with China, but also it has to find a major power to counter-balance China and its growing clout. I think this is how Burma wants to play a balancing game," he says.

What does the U.S. stand to gain?

In a recent article for Foreign Policy magazine, Clinton wrote of the importance of the Asia-Pacific region as a future focus for U.S. diplomatic relations.

"At a time when the region is building a more mature security and economic architecture to promote stability and prosperity, U.S. commitment there is essential," she wrote.

Obama has said the the U.S. remains "concerned about Burma's closed political system, its treatment of minorities and holding of political prisoners and its relationship with North Korea. But we want to seize what could be a historic opportunity for progress."

The secretary-general of the Association of Southeast Asian Nations, Surin Pitsuwan, has said the benefits of bringing Myanmar in from its political isolation extend far beyond the U.S.

"It's the beginning of a new chapter of the region because the integration of Myanmar into ASEAN more effectively and Myanmar into the international community will be a benefit for everyone," he said this month, as Asian nations endorsed Myanmar for the chairmanship of its regional grouping in 2014.

Is Myanmar really headed toward democracy?

Outside observers have expressed skepticism as to whether Myanmar's leaders are truly committed to providing greater freedom for its long-suffering people.

Human Rights Watch says the country continues to hold hundreds of political prisoners, and it has not repealed repressive laws on free speech and assembly.

"With this backdrop, it is too early to know whether the government's change of tone and talk of reform is cynical window-dressing or evidence that significant change will come to the country," the group wrote in a briefing paper.

"The reform is encouraging -- we should encourage it -- but I also think that some people have a doubt (and think) that the government is making small token gestures to gain international legitimacy. If that is the case, it would be very disappointing for a lot of people."